In line with our finding of ACPA positivity as a predictor of the “good responders” class, higher likelihood of early response (i.e., 4 months) to treatment with MTX in seropositive patients with abundant autoantibodies including ACPA was reported in the induction therapy with MTX and prednisone in RA or very early arthritic disease (IMPROVED) study [32]. The gene discussed is PRTN3; the disease is rheumatoid arthritis.